YUASA battery Guide - Was looking at a 'YTX' but then saw the GYZ - seems about the same performance but YTX has 'superior resistance to vibration' and superior something or other -
Best Motorcycle Batteries (Review & Buying Guide) | The Drive
YB12A-A - Yuasa Battery, Inc.
Everything you need to know / Motorcycle Batteries, Demystified - Adventure Rider